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In XDP_ZEROCOPY unaligned > mode the chunk offset is encoded in bits 48-63 of the descriptor > address (XSK_UNALIGNED_BUF_OFFSET_SHIFT = 48), meaning the offset is > lost entirely. The completion queue then returns a truncated address to > userspace, making buffer recycling impossible. > > Since we hear no one is using AF_XDP on 32-bit arch, we decided to > strictly stop supporting it at compile time. > > Closes: https://lore.kernel.org/all/20260419045824.D9E5EC2BCAF@smtp.kernel.org/ > Fixes: 0ebc27a4c67d ("xsk: avoid data corruption on cq descriptor number") > Suggested-by: Stanislav Fomichev > Signed-off-by: Jason Xing > --- > net/xdp/Kconfig | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/net/xdp/Kconfig b/net/xdp/Kconfig > index 71af2febe72a..819aa5795f50 100644 > --- a/net/xdp/Kconfig > +++ b/net/xdp/Kconfig > @@ -1,7 +1,7 @@ > # SPDX-License-Identifier: GPL-2.0-only > config XDP_SOCKETS > bool "XDP sockets" > - depends on BPF_SYSCALL > + depends on BPF_SYSCALL && 64BIT > default n > help > XDP sockets allows a channel between XDP programs and > -- > 2.41.3 > Acked-by: Stanislav Fomichev